Ditching machine having vertically adjustable wheels



Septl, 1970 E. ROESSLER ET AL 3,526,047

DITCHING MACHNE HAVING VERTICALLY ADJUQTABLE WHEELS Filed Oct. 9, 1967.4 Sheets-Sheet l Sept. 1, 1970 E ROESSLER ET AL 3,526,047

DITCHING MACHINE HAVING VERTICALLY ADJUsTABLE WHEELS .4 Sheets-Sheet 2Filed Oct. 9, 1967 IN VEN TORS my MKM .4 77'0RNEKS` .Il 4IlllI-l KENNETHP GOL TZ MART/N M. MEDLL/N EDMUND ROESSLER m, QQ mmwmm ow E E WHEELSSept 1, 1970 E. ROESSLER ET AL DITCHING MACHINE HAVING VERTICALLYADJUSTABL Filed Oct. 9, 1967 ,4 Sheets-Sheei 3 @L www,

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KENNETH P co1. rz MART/N M. MEDLL/A EoMu/vo RoEss/ EA /NVEN7ORJATTORNEYS Sept. 1, E. ROESSLER [TAL l DITCHING MACHINE HAVING VERTICALLYADJUSTABLE WHEELS Filed Oct. 9, 196'7 KENNETH l? GOL TZ MART/N M MEDLL/NE DMUND ROESSLER /NvE/vro/es MW )4M Arrowgrs United States Patent Oce3,526,047 Patented Sept. 1, 1970 3,526,047 DITCHIN G MACHINE HAVINGVERTICALLY ADJUSTABLE WHEELS Edmund Roessler, 2025 N. Archie, Fresno,Calif. 93703; Kenneth P. Goltz, 608 W. Scott, Clovis, Calif. 93612; andMartin M. Medllin, 820 Willis, Madera, Calif. 93637 Filed Oct. 9, 1967,Ser. No. 684,884 (Filed under Rule 47(b) and 35 U.S.C. 118) Int. Cl.E02f 5/02; B605 9/20; B62d 6]/12 U.S. Cl. 37-98 4 Claims ABSTRACT F THEDISCLOSURE A ditching machine for digging irrigation and drainageditches, canals and the like and for reforming and cleaning existingcanals of weeds and other extraneous material. The ditching machineincludes a wheel suspension system including vertically adjustablehydraulic cylinders which enables the machine to negotiate sloping banksduring entry into existing canals and during its exit therefrom withvirtually no danger of tipping. Laterally adjustable moldboards areprovided to allow the machine to form a Wide variety of differentconfigurations and sizes of canals. The machine is easily converted to arelatively narrow lateral dimension for highway transport.

Essentially, the present invention consists of a ditching machine whichis adapted to be propelled in a predetermined relative forward directionof earth traversing movement which incorporates a single tubular mainframe providing a machine support and a protective conduit for hydraulichoses, mechanical control linkages, and other related hardware. Theframe has predetermined forward and rearward ends and is supported bysets of earth engaging wheels at its ends with the wheels at therearward end of the frame being mounted for powered lateral movementtransversely of the longitudinal axis of the frame so as to be spacedfrom each other a distance corresponding to the width of the bottom ofthe ditch or canal and in equally spaced symmetrical relation to thelongitudinal axis of the frame. Such wheel mounting also enables thewheels to be selectively oppositely elevationally raised and lowered inspaced substantially parallel planes for maintaining the machinesubstantially upright while traversing the sloped sides of the ditch`banks during entry into the ditches and when exiting therefrom withouttipping. A plurality of hinged ditch forming blades are mounted on theframe intermediate its ends with the blades being adjustable through awide range of movement for digging a wide variety of ditch congurations.The blades are power operated between their various adjusted positionswhich permits the blades to be retracted to a position closely adjacentto the frame without pulling any hinge pins or the like so as to presenta minimum lateral dimension acceptable for highway transport of themachine and extended for maximum operational stability. An auxiliaryearth engaging frame support skid is mounted on the frame between theditch forming blades and the rearward end of the frame for additionalflotation when the machine is operating in loose, sandy or boggy soil.

Conventional ditching machines for the purpose described above usuallyprovide a plurality of ditch forming blades having only a narrowlylimited range of adjustable movement and include retractable pins andother rigid connector members which must be tediously removed andreplaced during blade adjustment. Such machines have relatively bulky,open, fabricated frames which expose their hydraulic hoses andmechanical control linkages and the like to possible damage. Thesemachines further employ suspension systems for mounting the wheels atthe rearward end of frames which employ only a single axle between therear wheels. The wheels are transversely positionable on such commonaxles so as to adjust the width of the track of the machines inconforming relation to the width of the bottom of the ditches with thewheels rollably engaging the adjacent sloping banks of the ditches formaximum stability. The single axles are pivotally mounted on theirframes intermediate their ends which has proven to be seriouslyunstable. For example, when the axles are pivoted relative to theirframes for elevationally spacing the wheels to maintain the machinesubstantially upright while traversing a sloping ditch bank, the lowerWheel is disposed beneath and during extreme conditions passes thelongitudinal center of the machine frequently causing the machine to tipover, particularly when the wheels are spaced closely together on theiraxles. The tipping of the axles corresponding displace the wheels fromtheir preferred upright positions. Furthermore, such conventionalmachines employ auxiliary support sleds which are usually mounted intrailing relation to their frames. Such mounting precludes pushing ofthe machines by a prime mover and requires that extension supportlinkage be provided to insure raising of the sleds to a sutlicientheight so as not to dig into the ditch banks when removing the machinesfrom the ditches.

Therefore, it is an object of the present invention to provide animproved ditching machine for forming, re-shaping or cleaning irrigationand drainage ditches, canals and the like.

Another object is to provide such an improved ditching machine which iscapable of forming a wider range of sizes and configurations of suchditches than heretofore possible.

Another object is to provide a ditching machine having a plurality ofpivotally mounted ditch forming or shaping blades which are poweractuated to adjusted positions.

Another object is to provide such blades which are retractable topositions closely adjacent to the frame of the machine to present aminimum lateral dimension acceptable for highway transport.

Another object is to provide such a machine which incorporates a wheelsuspension system having rear wheels which are transversely positionablerelative to the longitudinal axis of the machine.

Another object is to provide such a machine which maintains the wheelsin equally spaced symmetrical relation to the longitudinal axis of themachine during all such adjustment.

Another object is to provide such a ditch forming machine wherein therear wheels are elevationally positionable relative to each other in alltransverse positions.

Another object is to provide a ditching machine having an auxiliaryframe support sled disposed in such a position on the machine that whenretracted the sled does not present any restriction to the removal ofthe machine from the ditches or entrance of the machine into ditches.

Other objects and advantages of the present invention will subsequentlybecome more clearly apparent upon reference to the following descriptionand accompanying drawings.

In the drawings:

FIG. l is a top plan view of a ditching machine embodying the principlesof the present invention showing a pair of sets of opposite rearwardlydiverging ditch forming blades extended in operating position from themachine.

FIG. 2 is a side elevation of the ditch forming machine of FIG. 1 withportions broken away for illustrative convenience.

FIG. 3 is a transverse vertical section through the machine taken online 3 3 of FIG. 2 showing the machine disposed lwithin an irrigationditch or the like.

FIG. 4 is a somewhat enlarged rear elevation of the ditching machine ofthe present invention showing a suspension system for the rear wheelsthereof.

FIG. 5 is a transverse horizontal section through the suspension systemtaken on line 5-5 of FIG. 4.

FIG. 6 is a fragmentary front elevation of the suspension system ofFIGS. 4 and 5.

FIG. 7 is a transverse vertical section through the suspension systemtaken on line 7-7 of FIG. 6.

Referring more particularly to the drawings, a ditching machineembodying the principles of the present invention is shown having anelongated frame generally indicated by the reference numeral 10` whichis adapted to be propelled for earth traversement in a predeterminedforward direction of travel from right to left, as viewed in FIG. l. Theframe includes an elongated rearwardly disposed tubular main section 11and a forwardly disposed tubular section 12. As best shown in FIGS. land 2, the sections are normally substantially coaxially aligned and arepivotally interconnected at their adjacent ends for elevational swingingmovement through substantially upright planes about a pivot pin 14extended through the main section and through a pair of ears 1S on theforward section 12. The frame sections 12 and 11, respectively, provideopposite forward and rearward ends 17 and 18 for the frame with theframe having a longitudinal axis aligned with the direction of earthtraversing movement of the machine. A pair of sets of forward andrearward ground engaging wheels 20 and 21, respectively, are mounted onthe forward and rearward ends of the frame for supporting the frameduring such earth traversing movement.

An operators station, indicated by the reference numeral 25, is disposedintermediate the ends 17 and 18 of the frame 10 on the main section 11thereof above and immediately rearwardly of the pivot pin 14. Theoperators station includes a seat 26 and a control board 27 mounting aplurality of hydraulic control valves 28. The operators station ispreferably enclosed by an upwardly extended cage 30 covered with aprotective screen 32. An engine is mounted on a platform 36 secured tothe main section 11 of the frame between the operators station and therearward end 18 of the frame. The platform also mounts a hydraulic pump37 and iiuid supply tank 38 for supplying a flow of hydraulic fluidunder pressure to various controls on the machine which willsubsequently be described.

The forward set of wheels 20 are pivotally mounted in freely rotatablerelation about a vertical axis by a dolly type wheel mounting assemblygenerally indicated by the reference numeral 40. The wheels arerotatably mounted on a common axle 41 which is secured to a king pin 42by a saddle bracket 43. The upper end of the king pin provides a clevis45 embracing the forward end 17 of the frame and includes a forwardlyextended tongue mounting portion 47 having a pair of pin mounting holes48 therethrough. An elongated tongue 50 having a rearward bifurcated end52 is adapted to be selectively aligned with the mounting holes 48 forreceiving a connecting pin S3 therethrough. The tongue has an oppositeforward end 5S which is adapted to be connected to the drawbar of aprime mover, not shown. By selection of the proper mounting holes 48,the tongue is disposed in a substantially horizontal position dependingupon the height of the drawbar of the prime mover so as to provide aconstant draft force to minimize diving or washboarding effect on themachine during operation.

A plurality of ditch forming blades 60 are mounted in dependingrearwardly outwardly diverging relation from the main section 11 beneaththe operators station 25 and intermediate the forward and rearward ends17 and 18 of the frame. The ditch forming blades include a rigid leadinglister blade y62 which is substantially V- shaped when viewed in planand which is rigidly secured, as by bolting or the like, to the forwardend of the main section 11. The leading lister blade includes a lowershoe portion 64, a forward edge 66 and opposite rearwardly extendedoutwardly diverging wings -68 terminating in trailing edges 69 laterallyoutwardly spaced from the frame. The trailing edges of the leadinglister blade are held in predetermined diverging relation by a spacerplate 70 secured between the trailing edges and to the underside of themain section 11 of the frame as by welding or the like.

A pair of adjustable lister blades 72 are individually pivotally mountedin substantially coextensive relation from their respectively adjacentwings 68 of the leading lister blade 62. The adjustable lister bladesinclude lower shoe portions 73 disposed in coplanar relation with theircorresponding lower shoe portions 64 of the leading lister blade andforwardly disposed edges 7S inwardly extended in overlapping relationwith their respective trailing edges 69 of the leading lister blade. Theadjustable lister blades have outer soil conveying surfaces 76 whichcombine with the side wings 68 of the leading lister blade 62 to providea continuous rearwardly outward flow of soil therealong. Each of theadjustable lister blades provides a plurality of hinge mounting gussets78 having a hinge member 79 pivotally connecting its respectiveadjustable lister blade on the spacer plate 70 in laterally inwardlyspaced relation to the trailing edges 69 ofthe leading lister blade 62.The adjustable lister blades further include trailing edges 82 with eachhaving a dual hinge assembly 85 mounted on the inner surface thereofadjacent to its trailing edge. Each hinge assembly provides asubstantially upstanding hinge pin 86 and a rearwardly substantiallyhorizontal hinge plate 87.

A pair of hydraulic jacks 90 are disposed between the adjustable listerblades for concurrent swinging movement of the blades about their hingemembers 79 on the spacer plate 70. Each of the hydraulic jacks providesa cylinder end 92 pivotally connected to the main section 11 of theframe 10 and an opposite extendible-retractable rod end 93 pivotallyconnected to the inner surface of its respective adjustable lister bladeclosely adjacent to its lower shoe portion 73. In order to insureprecise corresponding swinging movement of the adjustable lister blades,a stabilizing linkage system 95 is disposed in expanding-contractinginterconnecting relation therebetween. The control linkage provides acentral lever 96 which is pivotally mounted intermediate its ends on adepending frame structure 97 and at its opposite ends is pivotallyconnected to the opposite inner surfaces of the adjustable lister bladesby links 98.

As best shown in FIG. 1, the lister blades 62 and 72 are raised andlowered with respect to the ground surface by elevational angularadjustment of the sections 11 and 12 of the frame 10. This isaccomplished by a hydraulic jack 100 having a cylinder end 102 pivotallyconnected to the front of the cage 30 of the operators station 25 and anextendible retractable rod end 103 pivotally connected by a pair ofbrackets 104 secured to the forward section 12 of the frame 10. This isaccomplished by a hydraulic rod end of the hydraulic jack 100, thesections of the frame are pivoted relative to each other and by rotarymovement of the forward section about the axle 41 of the front wheels20, the blades are lowered into deeper earth penetration.

A pair of elognated moldboards are individually extended for elevationaland lateral outward swinging movement from the trailing edges 82 of theadjustable lister blades '72. The moldboards include forward ends 112which are extended in inward overlapping relation to their associatedtrailing edges 82 of the adjustable lister blades 72 for pivotalconnection therewith by the dual hinge assemblies 8S. Hinge member 113is disposed adjacent to the forward end of each moldboard through whichthe hinge pin 86 is extended to provide a subtantially vertical pivotaxis. Each of the forward ends of the moldboards mounts a substantiallyhorizontally oriented pivot pin 114 which is extended through a bore inthe hinge plate 87 of its associated adjustable lister blade 72 andthrough the associated hinge plate 113 to provide a substantiallyhorizontal axis about which the moldboard is swung in its describedsubstantially vertical path of movement with such connection alsopermitting lateral swinging movement of the moldboard about the verticalhinge pin 86.

Such dual movement of the moldboards is accomplished with a pair of setsof upper and lower hydraulic jacks and 116, respectively. The upperjacks 115 provide cylinder ends 118 which are pivotally mounted inelevationally spaced relation above the frame on a tower structure 120upwardly extended from the main section 11 of the frame. The jacks 115include opposite rod ends 122 which are pivotally connected adjacent tothe lower edges of their respective moldboards for elevational swingingmovement of the moldboards relative to the frame. The lower jacks 116provide cylinder ends 125 which are pivotally connected to a dependingframe section 126 and opposite rod ends 128 pivotally connected to theirrespective moldboards above and in crossing relation with the rod ends122 of the upper jacks for effecting the described lateral swingingmovement of the moldboards.

Each of the moldboards 110 has an adjustable power actuated spoil wing130 pivotally connected at its outer end. The spoil wings areindividually pivotally mounted on an angularly related hinge assembly132 so that when the wings are longitudinally aligned with theirrespective moldboards as shown in FIG. l, the lower edges of the spoilwings are also coextensive with the lower edges of their respectivemoldboards. However, when swung laterally outwardly from the moldboard,as in FIG. 3, the lower edges of the spoil wings are angularly relatedto the lower edges of the moldboards and disposed in substantiallyhorizontal planes. Such movement of the spoil wings is provided by apair of hydraulic jacks 136 having cylinder ends 137 individuallypivotally mounted on brackets 138 secured to the inner surfaces of theirassociated moldboards 110. The jacks include opposite rod ends 140kwhich are pivotally connected to their respective wings by a pedestal142 extended therefrom.

An elongated skid or sled is disposed between the ditch forming blades60 and the rear wheels 21 for providing additional support for themachine when operating in loose, sandy or boggy soil. The sled ismounted in depending relation from the frame by a plurality of links 152which are pivotally mounted at their lower ends on the sled and at theiropposite upper ends on a plurality of arms 154 secured to the mainsection 11 of the frame 10. A hydraulic jack provides a cylinder end 162pivotally mounted beneath the frame on a pair of brackets 163 secured tothe underside of the frame and an opposite rod end 166 pivotallyconnected to the sled.

As best shown in FIGS. 4 through 7, the rear wheels 21 are mounted `tor'adjustment transversly of the longitudinal axis of the frame and forcorresponding opposite elevational adjustment by a wheel suspensionsystem generally indicated by the reference numeral 170. The suspensionsystem provides an elongated mounting column 172 disposed in upwardlyextended relation from the rearward end 18 of the frame. The upper endof the column is bifurcated to form forward and rearward plates 173 and174, respectively, which terminate in upper ends 176. An open box-likecross frame is mounted on the column between the forward and rearwardplates of the column and includes forward and rearward sides 182 and183, respectively, and opposite ends 185 which combine to dene anelongated rectangular horizontal passage 186.

A pair of wheel mounting carriages are disposed within the passage 186of the cross `frame 180. Each of the carriages provides sets of upperand lower rollers 192 and 193, respectively, rollably engaging the upperand lower edges of the sides 182 and 183 of the cross frame. Each of thecarriages provides a pair of spaced inner walls 195 which definetherebetween an elongated vertical guide passage 196. As best shown inFIG. 6, a pair of hydraulic jacks 200 are mounted in side-by-sideoppositely extended relation on the forward plate 173 of the column 172for effecting movement of the carriages 190 through the passage 186 inthe cross frame 180. The hydraulic jacks include cylinder ends 202 whichare secured to the forward plate 173 of the column 172 and opposite rodends 204 connected to their associated carriages. In order to insureopposite corresponding movement of the carriages, a stabilizing linkage210 is disposed in interconnecting relation between the carriages. Asbest shown in FIGS. 4 and 5, a central lever 212 is pivotally mountedintermediate its ends on the forward plate 173 within the passage 186.The opposite ends of the lever are individually pivotally connected tothe carriages by a pair of links 214.

A pair of elongated wheel mounting masts 220 are individually slidablyextended through the guide passages 196 in the carriages 190. Each ofthe wheel mounting masts provides a lower end 221 which is connected, asby welding or the like, to a wheel mounting skirt 224. A stub axle 225is mounted on the lower end of the skirt for rotatably mounting itsrespective wheel 21 for rotation about an independent substantiallyhorizontal axis. Each of the masts includes an upper end 227 which isbifurcated to mount a roller 228 on an elongated pin 229 which isextended through the roller and through the upper end of the mast in aposition to dispose the upper periphery of the roller above the upperend of the mast. As best shown in FIG. 7, the pin is longer than thewidth of the mast so as to provide outer extended portions 230.

An elongated rocker beam 235 is pivotally mounted between the upper ends176 of the forwardand rearward plates `173 and 174 of the column 172 ona pivot pin 236 extended therethrough. The rocker beam is of I-beamconstruction providing opposite sides 237 and a centrally disposedconnecting wall 238. The wall has a lower elongated roller engagingsurface 240 which provides a substantially `frictionless connectionbetween the upper ends of the masts and the rocker beam. A pair ofelongated rods 243 having outwardly arcuately upturned ends 244 aresecured, as by welding or the like, along the inner lower edges of thesides 237 of the beam for sliding engagement with the extended ends 230of the roller pins 229'. A pair of hydraulic jacks 250 provide cylinderends 252 which are individually secured in substantially upstandingrelation on the rear side 183 of the cross frame 180 by saddle brackets254. The jacks include lower rod ends 255 which are pivotally connectedto their respective wheel mounting skirts by a connecting bracket 256secured to the skirt.

As best shown in FIG. 6, a pair of hydraulic conduits 260 and 261 areconnected between the cylinder ends 252 and the rod ends 255 of thehydraulic jacks 250 for alternately supplying hydraulic uid underpressure to the jacks from the hydraulic pump 37. The conduits includebranch lines 262 and 263 which are connected to a pressure regulatingbypass valve 265. The valve provides a stern 266 and an upstandingcontrol lever 267 which has a lower end 268 pivotally connected to anarm 269 on the valve and an opposite upper end 270. The upper end of thelever is extended through the stem and into an opening in a controlplate 272. The control plate is connected to the rocker beam 235 forswinging movement therewith about the pivot pin 236. Accordingly, thebypass valve is actuated by the control lever 26-7 upon a predeterminedangular movement of the rocker beam from its substantially horizontalposition shown in FIG. 6. Upon actuation, the valve is effective tobypass hydraulic fluid to the jacks to limit their extent of extensionand retraction.

7 oPERAttoN The operation ot the described embodiment of the subjectinvention is believed to be clearly apparent and is briefly summarizedat this point. The draft tongue 50 is connected to the front wheelmounting assembly 40 by the pin 53 extended through the desired mountinghole 48 depending on the elevational location of ther drawbar on theprime mover, not shown. This enables the tongue to be disposed in asubstantially horizontal position so as to transmit the draft forcesfrom the prime mover to the ditching machine in a substantially straightline to minimize diving or upward movement of the blades. Duringtransport and entry of the ditching machine of the present inventioninto a ditch, the hydraulic jacks 90, 115 and 116 are retracted todispose the adjustable lister blades 72 and the moldboards 110 inclosely spaced relation to the frame 10. It is noted that the moldboardsare fully power operated and require no removal of hinge pins or thelike to dispose them in their adjusted angular positions relative to theframe. The sled 150 is also elevated by retraction of its associatedhydraulic jack 160 to provide maximum ground clearance. -In order toelevate the leading lister 62 and the adjustable listers 72, thehydraulic jack 100 is extended angularly to displace the forward section12 and the main section 11 of the frame so as to raise the forward endof the main section sufficiently that the machine is able to traversethe sloping banks of the ditch without any portions thereof dragging orgouging into the banks.

As the ditching machine enters the ditch, the adjacent sloping bankthereof is approached from an angle and as soon as the closer of therear wheels 21 rolls downwardly upon the bank, the hydraulic controlValves 28 are manipulated by the operator to provide a iiow of hydraulictiuid through the conduits 260 and 261 to extend the hydraulic jack 250to lower such wheel downwardly along the sloping bank and simultaneouslycorrespondingly to elevate the opposite wheel still engaged with thelevel portion of the ground adjacent to the ditch, Such relativemovement of the wheels is continued as both wheels engage the slopingbank in order to maintain the ditching machine in a substantiallyupright position. It should be noted that during each entry maneuver,the hydraulic jacks 200 are normally fully extended to position thecarriages 190 and the rear wheels in their maximum transversely spacedrelation for optimum stability.

As the downwardly disposed rear wheel 21 engages the bottom of theditch, the flow of hydraulic fluid through the conduits 260 and 261 isreversed to return the wheels to their substantially aligned positionsof FIG. 4 when the machine is fully disposed within the bottom of theditch. The adjustable lister blades 72 are then outwardly extended byactuation of their hydraulic jacks 90 so that the trailing edges 82 ofthe blades are separated a distance corresponding to the width of thebottom of the ditch. Upon forward movement of the machine, the hydraulicjacks 200 are extended or retracted transversely to position the wheelstoward or from each other in predetermined spaced relation correspondingto the width of the adjustable lister blades so that the wheels aredisposed against the lower portion of the ditch bank for maximum machinestability.

The lower hydraulic jacks 116 are then actuated to swing the moldboards110 outwardly from the frame. The moldboards are concurrentlyelevationally positioned by actuation of their upper hydraulic jacks 115precisely to conform the moldboards to the angle of the ditch banks. Thespoil Wings 130 are swung angularly outwardly from their respectivemoldboards to their level positions of FIG. 3 by actuation of theirhydraulic jacks 136 so as to direct soil outwardly from the ditch uponforward movement of the machine. The hydraulic jack 100 is thenretracted to lower all of the ditch forming blades 60 into earthpenetrating relation for moving the engaged soil rearwardly outwardlyalong the outer conveying surfaces 68 and 76 thereof'and outwardly ofthe ditch during forward movement of the ditching machine by the prim'emover. The sled 150 is lowered by extension of its hydraulic jack 160 toa position approximately one inch above the plane of the lower peripheryof the wheels. Accordingly, any penetration of the wheels which exceedssuch spacing brings the lower surface of the sled into ground engagementfor increased support of the machine during movement vover loose, sandyor boggy soil. It is noted that the relative elevational position of therear wheels 21 can be adjusted during operation by actuation of theirhydraulic jacks 250 transversely to tip the frame to either side ifnecessary to clear overhead obstructions such as low-hanging tree limbs,irrigation canal headgates or the like.

After completion of the ditch forming, shaping or cleaning operation,the ditching machine of the present invention is easily removed from theditch by reversing the above described procedures for entry of themachine into the ditch. The hydraulic jack is extended to lift the ditchforming blades 60. The hydraulic jack 160 is retracted to raise the sled150 to a position providing sutiicient ground clearance so as not togouge into the side bank of the ditch. The adjustable lister blades 72and the moldboards are retracted by actuation of their hydraulic jacks90, and 116 to position them closely adjacent to the frame. The ditchingmachine is then drawn diagonally upwardly along the sloping ditch bankand the rear wheels elevationally staggered in conforming relation tothe slope again to maintain the frame in a substantially uprightposition during traversernent of the ditch bank.

It is noted that during elevational positioning movement of the rearwheels 21 the wheels are conned to a rectilinear path of travel and aremaintained the same lateral distance from the longitudinal axis of theframe when either raised' or lowered. Accordingly, the rear wheels arealways maintained in equally spaced symmetrical relation with respect tothe longitudinal axis of the frame as opposed to conventional ditchingmachines having only a single common rear axle which pivots on the frameto raise and lower the wheels so that the lower wheel shifts to anunstable position beneath the frame, causing tipping. Furthermore, suchsymmetrical relationship of the rear wheels is maintained irrespectiveof the transverse spacing of the wheels by the stabilizing linkage 210.

As previously described, the bypass valve 26S is operative to limit theextent of the travel of the hydraulic jacks 250 so as to limit theextent of relative elevational movement of the wheels from their alignedpositions of FIG. 4. With the wheels disposed in their maximumtransversely separated positions of FIG. 4, the lever arm formed betweenthe pivot pin 236 of the rocker beam 235 and the rollers 228 of thewheel mounting mast 220 permits substantially full extension andretraction of the jacks 250 for maximum elevational displacement of thewheels prior to actuation of the bypass valve 265. It is noted that withthe wheels in such maximum transversely spaced relation, fullelevational displacement of the wheels is acceptable `without impairingthe stability of the machine and resistance against tipping. However,with the wheels positioned transversely closer together, machinestability would be adversely affected if full extension and retractionof the hydraulic jacks 250 were permitted. It will be apparent, however,that when the wheels are moved closer together, the effective lever armbetween the pivot pin 236 and the rollers 228 is reduced so that uponactuation of the bypass valve 265 with the same angular movement of therocker beam the relative elevational movement of the wheel mountingmasts is correspondingly reduced. Consequently, full extension andretraction of the jacks 250 is prevented, thus limiting the elevationaldisplacement between the rear wheels to maintain stability of theditching machine and to resist tipping. Accordingly, the Wheels cannever be elevationally displaced from each other any amount exceedingthat which will maintain the machine in a substantially upright stablecondition.

In view of the foregoing, it is readily apparent that the structure ofthe present invention has provided an improved ditching machine which isfully pwer operated and requires no manual positioning of the ditchforming blades thereof as is necessary with conventional machines. Theditch forming blades are capable of being disposed closely adjacent tothe frame so as to provide a minimum transverse dimension acceptable forhighway transport. Furthermore, the present invention includes asuspension system for the rear wheels of the machine which enables thewheels to be elevationally displaced in staggered relation to each otherfor maintaining the machine in a substantially upright position whiletraversing the sloping banks of ditches. Also, the flotation sled ismounted on the frame between the wheels which requires only a minimum ofretractable movement to dispose the sled in a position to providesuihcient ground clearance to minimize dragging or gouging into theditch banks during entry of the machine into the ditches and during itsexit therefrom.

Having described our invention, what we claim as new and desire tosecure by Leters Patent is:

1. A ditching machine adapted to be propelled in a predetermined forwarddirection of ground traversement comprising an elongated main framehaving predetermined forward and rearward ends including an elongatedrearwardly disposed tubular main section and a forwardly disposedtubular section pivotally connected to said main section insubstantially coaxial relation therewith and in substantiallylongitudinal alignment with said direction of movement; a pair of setsof ground engaging wheels individually mounted on said tubular sectionsof the main frame; ditch forming means mounted on the main frameintermediate its ends; auxiliary ground engaging support means mountedon the main frame between said ditch forming means and said rearward endof the main frame; powered means disposed in bridging intercon nectedrelation between said sections of the main frame for angularly adjustingthe sections to raise and to lower said ditch forming means relative tothe ground; guide means having a cross frame disposed above the rearwardend of the main frame mounting one set of said wheels; a pair ofcarriages rollably mounted on the cross frame; and control meansconnected to said guide means for selective elevational movement of thewheels in opposite direction relative to each other and for movement ofthe carriages and the wheels toward and away from each othertransversely of the longitudinal axis of the frame, said guide meansincluding a pair of elongated support masts individually elevationallyslidably extended through said guide carriages for movement in arectilinear path of travel having lower wheel mounting ends and oppositeupper ends extended above said cross frame, said main frame having anupright portion extended from the rearward end thereof supporting saidcross frame above the main frame and having an upper end elevationallyspaced from the cross frame, an elongated rocker arm having oppositeends pivotally mounted intermediate its ends on said upright portion ofthe frame and providing a track slidably engageable with the upper endsof the masts to permit said transverse movement of the mast and wheelsand to insure correspondingly opposite elevational reciprocal movementof the wheels during said elevational positioning.

2. The ditching machine of claim 1 including powered means on the frameconnected to said carriages for effecting said transverse movement ofthe mast and wheels, and linkage means disposed between the masts toinsure said corresponding movement of the Wheels toward and away fromeach other in precise equally spaced symmetrical relation to thelongitudinal axis of the frame.

3. The ditching machine of claim 2 including powered means mounted onthe carriages for connection to said lower wheel mounting ends of themasts and being connected to said control means for selective raisingand lowering of the wheels in opposite directions relative to eachother, said control means including a fluid bypass valve on said upperextension of the frame, and indicator means on the rocker arm connectedto said bypass valve for movement with the rocker arm to providepredetermined limits of said elevational reciprocal movement of thewheels irrespective of the transverse position of the wheels so thatwhen the wheels are positioned relatively close together relativelyshorter effective lever arms are provided between the pivot of therocker arm and the upper ends of the masts substantially to reduce theamount of relative elevational travel of the wheels.

4. In a vehicle having an elongated frame and a pair of ground engagingframe support means spaced longitudinally thereof, means mounting theframe on one of said support means for substantially transverse tippingwith respect to ground traversed thereby, and the other of said supportmeans comprising a pair of axially spaced support wheels, means mountingthe frame on said support wheels with the wheels substantially equallyspaced on opposite sides of the longitudinal center line thereof, saidmeans mounting the frame on the support means providing a cross frame,an upright member mounting said cross frame on the vehicle frame in-upwardly spaced relation therefrom and including an upper endelevationally spaced above said cross trarne, a pair of carriagesrollably mounted on the cross frame, a pair of elongated support mastsindividually elevationally slidably extended through said carriages formovement in a rectilinear path of travel having lower wheel mountingends and opposite ends extended above said cross frame, and an elongatedrocker arm having opposite ends pivotally mounted intermediate its endson said upper end of the upright member and providing a track slidablyengageable with the upper ends of the masts to permit substantiallyequal axial adjustment of the wheels toward and from said center line ofthe frame to control the stability of the support provided therebytransversely of the frame and for substantially equal and oppositeelevational adjustment of the wheels relative to the frame whileconstraining the wheels in substantially parallel relation to controlthe transverse attitude of the frame relative to ground traversed bysaid wheels.

References Cited v UNITED STATES PATENTS ROBERT E. PULFREY, PrimaryExaminer C. D. CROWDER, Assistant Examiner U.S. Cl. X.R.

